Answer: D - A service sink, also known as a utility sink, is specifically designed for tasks that are more utility-oriented and involve cleaning that might not be suitable for kitchen or bathroom sinks. Therefore, the correct use for a service sink is for cleaning mops and throwing out waste water, which corresponds to option D. It is intended for handling tasks that require dealing with potentially dirty or contaminated water that should not be mixed with areas used for personal hygiene, food preparation, or eating. This ensures that hygiene standards are maintained, preventing cross-contamination between cleaning and food prep or first-aid areas. Options A, B, and C are not appropriate uses for a service sink, as they involve activities that should be carried out in sinks designated for those specific purposes to maintain sanitary conditions.
